摘要本论文以 3Cr2W8V 热作模具钢为原料,采用新研制的第二代旋转加速喷丸设备对其进行表面纳米化处理,之后测定处理表面粗糙度、横截面硬度并观察其微观组织。主要结论如下:可以实现纳米化,表层晶粒尺寸在 100nm 以下。在处理过程中,一定范围内,随着处理时间的增加,表面粗糙度也会有所增加。材料表面粗糙度整体比较均匀。进行 60min 处理后,在其最表面大约 50μ m 范围内实现了纳米化,最表面的硬度达到了 658HV,明显高于未处理前的 566HV,增幅为16%。TEM 观察表面晶粒尺寸在 100nm 以下,并有高密度的位错组织,细晶强化和加工硬化是其高硬度的主要原因。19197
关键词 3Cr2W8V 表面纳米化 微观结构 硬度
Title Research on the surface nanocrystallization of hot die steel
Abstract
In this work,a hot-working 3Cr2W8V tool steel was subjected to a process
of surface nano-crystallization by using second generation of Rotation
Accelerated shot peening. The roughness of the treated surface and hardness
of cross-section were measured and the microstructures were observed. The
following conclusions can be drawn : Firstly, through the method,
nanocrystallization can be achieved, and the averaged surface grain size
is smaller than 100 nm. Additionally, during the processing procedure, the
surface roughness increases with the treatment time growing. Especially,
the roughness behaves relatively uniform distributed overall the materials
surface. After 60 minutes treating, nanocrystallization is realized in the
range of 50 μ m near the surface. More importantly, the hardness of the
surface increases by 16% to 658 HV, obviously higher than 566 HV of
untreated samples. In the end, the results of TEM verify that the grain
size is nanoscale and there is high density of dislocation structures near
the surface. Fine-grain strengthening and work hardening contributed to
the high hardness phenomenon.
Keywords 3Cr2W8V Surface nano-crystallization Microstructure Hardness
目 次
1 绪论 . 1
1.1 热作模具钢的简介 1
1.2 纳米材料的简介 1
1.3 纳米材料的制备 3
1.4 塑性变形致金属材料表面纳米化 4
1.5 金属材料表面纳米化技术优势 6
1.6 钢铁材料表面纳米化 7
1.7 本文研究内容 7
2 实验部分 . 8
2.1 实验材料 8
2.2 试样制备过程 8
2.3 处理后表面粗糙度的测定 9
2.4 金相实验 9
2.5 硬度的测定 9
2.6 透射电镜实验 10
3 实验结果与讨论 . 12
3.1 表面纳米化样品制备 12
3.2 金相分析 13
3.3 粗糙度 17
3.4 硬度 22
3.5 TEM . 25
结 论 . 28
致 谢 . 29
参考文献 . 30
1 绪论
1.1 热作模具钢的简介
模具在机械、冶金、电子、轻工、国防[1]
等工业部门中扮演着重要的角色,保证
了生产的高效率,保证了产品的高质量的同时又使得生产成本大幅度降低。在工业技
术迅猛发展的形势下,效率高、精度高的模具成型工艺得到了空前广泛的采用,并逐 热作模具钢表面纳米化研究+文献综述:http://www.751com.cn/cailiao/lunwen_10470.html